The dish is composed of a set of 10 inch by 12 foot curved mirrors, like the one seen here. The students easily mount the mirrors to the aluminum framework using simple hardware like washers and zip ties. (Source: MIT)

The mirrors incredible power makes short work of a beam of wood, disintegrating it in flames and smoke. The focal point can melt steel. (Source: MIT)

The solar industry is booming. With waves
of investment and grants,
the solar power industry is for the first time becoming a serious
business. New
power plants will soon be pumping power out to consumers, while other firms
market to sell panels directly
to the consumer, providing them with a more direct means of experiencing
solar energy.

There are many forms of solar power technology. Today the most dominant
is photo-voltaics,
which comprise the traditional solar panels that come to mind when one thinks
of solar power. However, there are other promising ways of capturing the
sun's energy that are merely less developed.

Among these is a parabolic collector. A parabolic collector consists of
an array of mirrors focused on a singular point, which they heat to a high
temperature. By placing water or another liquid at the collector, energy
can be stored in the form of a phase transformation, and later harvested
through a turbine generator.

However, parabolic collectors are still a relatively new field of research.
Their true potential remains relatively unknown. A glimpse of it was
provided by a research team at MIT, which developed a new parabolic collector
design, which will blow away
current solar power designs in terms of efficiency.

The MIT team believes that their lightweight, inexpensive device holds the
promise of revolutionizing the power industry and providing solar power to even
remote regions.

The key piece is the 12-foot dish, which the team assembled in several
weeks. The design is exceedingly simple and inexpensive. The frame
is composed of aluminum tubing and mirrors are attached to it.

The results are staggering -- the completed mirror focuses enough solar energy
at its focal point to melt solid steel. The energy of typical sunlight is
concentrated by a factor of 1,000. This was showcased during a
demonstration, in which a team member held up a board, which instantly and
violently combusted, when brought within range of the focal point.

By directing the dish at a more practical target -- water piped through black
tubing -- steam can be flash created, offering instant means of producing
energy or providing heating.

Spencer Ahrens, who just received his master's in mechanical engineering from
MIT, was among the designers of the dish. He and his fellow team members
are serious about marketing it, and leveraging its cheap cost and easy
production. They have founded a company named RawSolar. They say
their design is easily mass producible and that they hope to be pumping
out 1,000 of dishes in years to come.

The new dishes would return their costs in a mere couple years, unlike standard
photo-voltaic installations which can take 10 years or more to return their
costs. This improvement is critical to providing practical economic
justification for adoption.

The dish is based partly on components invented and patented by inventor Doug
Wood. He was so pleased with the team's work that he signed over rights
to the components to the team. He elates, "This is actually the most
efficient solar collector in existence, and it was just completed. They
really have simplified this and made it user-friendly, so anybody can build
it."

Wood says one of the keys to the success of the project is the smaller
size. Dishes are affected by the same weight dynamics that effect living
organisms. Much as large living organisms would need an inordinate amount
of weight support and thus are not favored, larger dish designs fall short in
that they require an exponentially greater amount of infrastructure. For
example, a dish the size of the RawSolar team's design costs only a third of what a larger dish would cost.

MIT Sloan School of Management lecturer David Pelly gave a guiding hand to the
students and thinks the economic upsides of the technology are
impressive. He states, "I've looked for years at a variety of solar
approaches, and this is the cheapest I've seen. And the key thing in scaling it
globally is that all of the materials are inexpensive and accessible anywhere
in the world. I've looked all over for solar technology that could scale
without subsidies. Almost nothing I've looked at has that potential. This
does."

The ability to build unsubsidized, profitable, and easy to manufacture solar
power will truly be something amazing. This should be an exciting
technology to follow as it is marketed and further developed.

I don't know whether this is new or not, nevertheless I worked it out 20 years ago. Showed it to a country neighbor once, he said, "Oh yeah. I read about that in a magazine."

Forming the Greek parabola:Start with a 4x8 sheet of plywood, drive a nail in lower left corner of the long side.Tie one end of an 8' string to the nail, double the string, (now 4') and put your pencil in the loop of the string.Hold one end of the string at the nail and the other end with the pencil at the upper left side of the plywood.Move the free end of the string along the bottom side of the plywood and the pencil to the right, maintaining a right triangle relationship between the nail, the pencil and the free end of the string.As you move the pencil and the free end of the string to the right, you will be drawing a curved line describing the point of the opposite side and the hypotenuse. As the opposite side of the triangle moves away from the nail, the opposite side diminishes as the base and the hyoptenuse increase. The relationship amoung the sides remains constant. When you end up with your 8' string at the lower right corner of the plywood, you will have half a parabola described across the sheet of plywood. The focal point is the nail.